1 /*

     2 * Copyright (c) 2003-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 *

    16 */

    17 

    18 

    19 #include <asymmetric.h>

    20 #include <asymmetrickeys.h>

    21 #include <bigint.h>

    22 #include <cryptostrength.h>

    23 #include <securityerr.h>

    24 #include <cryptopanic.h>

    25 #include "rsafunction.h"

    26 

    27 /* CRSAPKCS1v15Decryptor */

    28 

    29 EXPORT_C CRSAPKCS1v15Decryptor* CRSAPKCS1v15Decryptor::NewL(

    30 	const CRSAPrivateKey& aKey)

    31 	{

    32 	CRSAPKCS1v15Decryptor* self = NewLC(aKey);

    33 	CleanupStack::Pop(self);

    34 	return self;

    35 	}

    36 

    37 EXPORT_C CRSAPKCS1v15Decryptor* CRSAPKCS1v15Decryptor::NewLC(

    38 	const CRSAPrivateKey& aKey)

    39 	{

    40 	CRSAPKCS1v15Decryptor* self = new(ELeave) CRSAPKCS1v15Decryptor(aKey);

    41 	CleanupStack::PushL(self);

    42 	self->ConstructL();

    43 	return self;

    44 	}

    45 

    46 TInt CRSAPKCS1v15Decryptor::MaxInputLength(void) const

    47 	{

    48 	return iPrivateKey.N().ByteCount();

    49 	}

    50 

    51 TInt CRSAPKCS1v15Decryptor::MaxOutputLength(void) const

    52 	{

    53 	return MaxInputLength() - iPadding->MinPaddingLength();

    54 	}

    55 

    56 void CRSAPKCS1v15Decryptor::DecryptL(const TDesC8& aInput, 

    57 	TDes8& aOutput)const

    58 	{

    59 	__ASSERT_DEBUG(aOutput.MaxLength() >= MaxOutputLength(), User::Panic(KCryptoPanic, ECryptoPanicOutputDescriptorOverflow));

    60 	__ASSERT_DEBUG(aInput.Length() <= MaxInputLength(), User::Panic(KCryptoPanic, ECryptoPanicInputTooLarge));

    61 

    62 	RInteger input = RInteger::NewL(aInput);

    63 	CleanupStack::PushL(input);

    64 

    65 	RInteger output;

    66 

    67 	RSAFunction::DecryptL(iPrivateKey, input, output);

    68 	CleanupStack::PushL(output);

    69 

    70     TPtrC8 ptr = *(output.BufferLC());

    71     iPadding->UnPadL(ptr, aOutput);

    72 

    73     CleanupStack::PopAndDestroy(3, &input); //BufferLC(), output, input

    74 	}

    75 

    76 CRSAPKCS1v15Decryptor::CRSAPKCS1v15Decryptor(const CRSAPrivateKey& aKey)  

    77 	: iPrivateKey(aKey)

    78 	{

    79 	}

    80 

    81 void CRSAPKCS1v15Decryptor::ConstructL(void)  

    82 	{

    83 	iPadding = CPaddingPKCS1Encryption::NewL(MaxInputLength());

    84 

    85 	// Check if MaxInputLength() makes sense, if not the key length must 

    86 	// be too small

    87 	if(MaxOutputLength() <= 0)

    88 		{

    89 		User::Leave(KErrKeySize);

    90 		}

    91 

    92 	TCrypto::IsAsymmetricWeakEnoughL(iPrivateKey.N().BitCount());

    93 	}

    94 

    95 CRSAPKCS1v15Decryptor::~CRSAPKCS1v15Decryptor(void)  

    96 	{

    97 	delete iPadding;

    98 	}